Comments on: Exploring iPhone Audio Part 1

By: Tom

Tom — Tue, 02 Jun 2009 13:10:48 +0000

This is a great article, but it does fail to mention two things in setting up for this code:

1. You have to add the Audio Tool box include files
2. You have to add the Audio Toolbox Framework to your project (for the linker)

By: Josh

Josh — Mon, 03 Nov 2008 06:47:43 +0000

Hi, has anyone tried to play two audio files at the same time? if you are asking why I need this, is to make the fade out of the current song while a new one starts playing. I have tried different things with no success on the phone (it worked on the simulator). any help would be greatly appreciated.

By: nebos

nebos — Wed, 03 Sep 2008 21:31:58 +0000

any way to control the audio input, or is the built-in mic the only option (is there an audio line input in the UDC?)

any way to control the actual gain of said input to compensate for very loud sounds in the external environment?

By: Gilbert Mackall

Gilbert Mackall — Sun, 17 Aug 2008 01:35:15 +0000

Can’t get the iPhone to accept this description

aqData.mDataFormat.mSampleRate = 8000.0;
aqData.mDataFormat.mFormatID = kAudioFormatLinearPCM;
aqData.mDataFormat.mFormatFlags = kAudioFormatFlagIsFloat | kAudioFormatFlagIsBigEndian ;
//aqData.mDataFormat.mFormatFlags = kAudioFormatFlagIsSignedInteger| kLinearPCMFormatFlagIsPacked;
aqData.mDataFormat.mFramesPerPacket = 1;
aqData.mDataFormat.mChannelsPerFrame = 1;
aqData.mDataFormat.mBitsPerChannel = 32;
aqData.mDataFormat.mBytesPerPacket = 4;
aqData.mDataFormat.mBytesPerFrame = 4;

By: peeInMyPantz

peeInMyPantz — Mon, 28 Jul 2008 18:23:26 +0000

what do I need modify to let this code play AMR file?

By: Exploring iPhone Audio Part 2 | Trails in the Sand

Exploring iPhone Audio Part 2 | Trails in the Sand — Wed, 26 Mar 2008 19:35:28 +0000

[...] Last time we created the RecordState structure to keep track of the recording state. We also configured the recording parameter to record 8000 samples per second, 16 bit, mono audio. [...]